Currently the U.S. Army is investigating methods to remove unexploded shells from artillery ranges and secured battle zones. One promising method uses remotely controlled vehicles having robotic accessories for shell removal. Since the vehicles will perform highly risky operations, it is likely that they will be damaged or destroyed with some regularity. It is therefore preferred that such vehicles be as cheap and expendable as possible. One practical and relatively inexpensive way to obtain such vehicles is to modify small commercially available off-road vehicles. It is preferred that these modified vehicles be capable of both manual and robotic operation. To meet part of the requirements Just related, we have invented an adapter subassembly that modifies adapts an existing manual throttle control device for manually overridable, powered, remotely controlled operation. Our subassembly is built of common, commercially available items and materials, so that the subassembly can be made inexpensively and without sophisticated manufacturing methods.
The modified throttle control device has a housing element, a post rotating in the housing element, and a manual control lever connected to the post. The lever rotates first and second rotor plates in a first direction about the post, thereby moving a cable engaging the second plate to a throttle-open position. A return spring biases the second plate in a second, opposite direction so as to bias the cable toward a throttle-closed position. Terminal elements of a throttle shut off switch are on the plates. The plates are biassed apart so that the switch is biased to an open, shut-off condition. Consequently, the switch will always shut off fuel flow to the engine unless force is positively applied to the control lever.
The adapter subassembly has a clear flat block-like cap removably affixed to the housing element, the cap having a cavity open toward the housing element. An actuator motor demountably secured to the cap rotates a paddle in the first and second directions, the actuator motor having a backdrive force less than the bias of the return spring. A flange of the paddle engages the tip of a tab, which is the terminal element on the first rotor plate. The flange is oblique to the tab and juxtaposed therewith such that the paddle's rotation in the first direction moves the rotor elements but the paddle's rotation in the second direction exerts no force on the rotor elements.